Automatic current digital control method based on CAN bus communication

Abstract

The invention discloses an automatic current digital control method based on CAN bus communication. In a main-driven competition mechanism, each of the N+1 parallel power supply modules publishes self information through CAN communication; each power supply can compete to be the main machine or the driven machine; about the main and the driven machine based on the competition mechanism, the main machine gives up a current feedforward ring, and takes an output positive-negative parallel bus pressure as the reference, and adjusts self output load current through a PID controller; the driven machine is added to the current feedforward ring, and adjusts self output load current to make the self output current value the same with the load current value of the main machine; each power supply module controls its load current itself to realize automatic current; if some power supply module has a fault, the power supply module quits work automatically, and the rest machines compete for main-driven machine again, which has no influence to the current sharing control system and the power supply system at present, overcomes the technology defect of redundant N+1 backup to the parallel power supply system in power supply technology field.

Description

technical field [0001] The invention relates to the technical field of power supplies, in particular to a parallel current sharing method for power supply modules. Background technique [0002] The existing analog current sharing schemes mainly include: characteristic drooping method: by increasing the output impedance, different modules have relatively close output characteristics, so that the goal of current sharing will cause the output characteristics to become softer, and the voltage adjustment rate is very low. Low. Master-slave configuration method: the master works in voltage mode, and its current reference is sent to all modules; all other slave modules work in current mode, which is too dependent on the master module. When the master module fails, the system directly crashes. Maximum current automatic current sharing method: the current value of the maximum current module appears on the current sharing bus; the maximum current module will automatically become the ...

AI Technical Summary

Problems solved by technology

Maximum current automatic current sharing method: the current value of the maximum current module appears on the current sharing bus; the maximum current module will automatically become the master module, and its current information will automatically appear on the current sharing bus, and the other modules will automatically become slave modules, but The main module will be changed alternately, so the output current of the module has obvious disturbance

[0003] In the existing digital current sharing scheme, the average load current value of the system is calculated through the communication data between the current sharing controller (monitoring module) or the power module, and each power module actively adjusts its own output load according to the calculated average load current value Current to achieve the purpose of current sharing. This solution is limited to the communication data between the current sharing controller (monitoring module) and the power module to calculate the average load current value. If the current sharing controller (monitoring module) fails, the current sharing system will collapse; If the modules are disturbed, the transmission data is wrong, and the current sharing system collapses; at the same time, the calculation accuracy and speed of the average load current value calculated by the power module limit the system current sharing accuracy and dynamic response speed

Therefore, there is a great technical risk in the existing technology

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